Sindel M, Hofstetter W, von Delft J, Kindermann M
Physics Department, Arnold Sommerfeld Center for Theoretical Physics, and Center for NanoScience, Ludwig-Maximilians-Universität München, Germany.
Phys Rev Lett. 2005 May 20;94(19):196602. doi: 10.1103/PhysRevLett.94.196602. Epub 2005 May 19.
We study the ac conductance and equilibrium current fluctuations of a Coulomb-blockaded quantum dot in the Kondo regime. To this end we have developed an extension of the numerical renormalization group suitable for the nonperturbative calculation of finite-frequency transport properties. We demonstrate that ac transport gives access to the many-body resonance in the equilibrium spectral density. It provides a new route for measuring this key signature of Kondo physics, which so far has defied direct experimental observation.
我们研究了近藤区中库仑阻塞量子点的交流电导和平衡电流涨落。为此,我们开发了一种数值重整化群的扩展方法,适用于有限频率输运性质的非微扰计算。我们证明,交流输运能够探测平衡谱密度中的多体共振。它为测量近藤物理的这一关键特征提供了一条新途径,而这一特征迄今为止一直难以通过直接实验观测到。